I have 3 Dremels, and many accessories. It is sometimes frustrating to find the accessory will not work with the Dremel most appropriate for the job.
For example the Dremellite is great for use in awkward places, where normal light is poor, (under the sink for example). The ideal Dremel for this is the cordless Lithium Ion one, but the Dremel light will not fit on this. A correct size washer would do the job.
Also accessories like the Jig Saw and Planer attachment would be great if they worked with the cordless model for convenience - it is a bit of a wire tangle to get the corded Dremel to that warped door on the terrace ! It would be ideal if every accessory worked with every model.